Preheat oven to 200°C or 180°C fan-forced. Line a baking tray with baking paper. Wrap beetroot in foil, place on prepared tray. Lay carrots on same tray, drizzle with 1 tablespoon of oil and season well. Bake for 30 minutes, until tender. Cool slightly.
Meanwhile, heat 1 tablespoon of the oil in a large frying pan over high heat. Cook lentils, stirring occasionally, for 10 minutes, until crisp and dry. Set aside to cool
Peel beetroot and cut into thick wedges. Arrange watercress on a platter, top with carrots and beetroot wedges. Crumble over goats cheese, drizzle over remaining oil and top with crisp lentils and pepita seeds